What makes a single-wall stainless steel water bottle toddler-approved?

It hits the three things that actually matter: indestructible, leakproof, and toddler-operable. My kid has dropped it off the kitchen table, thrown it out of the stroller, and used it as a hammer — and it still looks new. The straw lid is simple enough for little hands to work independently, and I’ve never found a damp spot in the backpack.